Figures from politics and showbusiness have paid tribute to "the brightest light in the Scottish political sky" at a celebration of the life of late nationalist veteran Margo MacDonald.

Ms MacDonald - who was known throughout Scotland simply as Margo - died on April 4 aged 70.

Edinburgh city centre was gridlocked as friends and political opponents made their way to the Assembly Hall on the Mound - which was the first home of the reconvened Scottish Parliament that she played a pivotal role in creating.

First Minister Alex Salmond sat shoulder to shoulder with leaders of all of Scotland's political parties and both sides of the independence divide.

Better Together leader Alistair Darling, Conservative Scotland Office minister David Mundell, former Labour First Minister Lord McConnell and Holyrood Presiding Officer Tricia Marwick were among those who gathered for the colourful celebration of her life.

Ms MacDonald spent her final days talking nationalist strategy with her husband Jim Sillars, and with the First Minister, who spent long periods by her bedside.

Mr Sillars and her close friend Alex Neil, Scotland's Health Secretary, delivered moving tributes and a message for Scotland as it prepares to vote in the independence referendum on September 18.

Mr Sillars said: "She gave me instructions to keep campaigning, and discussed with me her concern for Scotland's people after the referendum result.

"She knew only too well that this nation is divided on the issue of independence.

"It was typical of Margo that she knew she was not going to be here to be concerned about this nation after the referendum to still be concerned in the last weeks of her life.

"At 10.01pm on September 18, whatever the result, she wanted those divisions to end and this nation to seek a unity of purpose.

"I bring a message from Margo to all engaged in the campaign: 'There will be harsh statements on both sides, the debate will be fierce, there will be verbal wounds inflicted, but if we conduct ourselves in the run-up to September 18 the Margo MacDonald way, the division will be much easier to heal'.

"The Margo MacDonald way is to recognise that you are dealing with opponents not enemies, not with ogres but with fellow human beings with whom you can disagree but must do so without malice."

Ms MacDonald, who suffered from Parkinson's disease, was the "blonde bombshell" who scored an early SNP victory in Govan in 1973 and was an inaugural SNP MSP in the first Scottish Parliament in 1999.

Following a dispute with the party she won three landmark election victories as an independent, beloved in the Lothians for her support for many causes, including calls for assisted suicide to be legalised.

Mr Sillars added: "Most knew that Margo was plagued by ill health but very few knew that she was never free from pain.

"There were two Margos - one that was known to the public as evidenced by the attendance here today and the avalanche of mail our family have received from all parts of the British Isles and beyond.

"There was also a private Margo who belonged to us. She was the mothership of our family.

"Her young years were steeped in the anxieties that can afflict a one-parent family, like living in a caravan and experiencing the humiliation that can go with poverty.

"The experience informed Margo's outlook on life but she never fell into the trap that others have done, mostly those who look in on but never experience poverty, in believing that because she escaped there was no reason why others could not do the same.

"She knew the crushing power of poverty on the human mind, body and soul and the determination to help people whose lives were scarred by it was a driving force throughout her life.

"Margo, whose heart was as big as Arthur's Seat, really cared about people.

"The Scotsman described her as a national treasure. When that star that was born in 1943 fell to Earth in April 2014, the brightest light in the Scottish political sky went out."

"I love that argument, and Margo was somebody who exemplified that ability to argue, to make her point rightly without a shouting match and then have the ability to have a laugh and maybe a wee song - a country song of course."

She added: "I love (journalist) Gerry Hassan's quote that for his parents being Scottish 'was something that you had to get over'.

"There's that thing that you were brought up with in Scotland that you don't get above yourself. Well, I'm happy to say Margo got well and truly above herself.

"I've always wanted to make a film about Margo winning Govan and maybe someday somebody will do it, because it's a really pivotal moment in history in Scotland.

"I told Margo that one night and she thought it was a hilarious idea."

Mr Neil said: "The turnout today here is testimony not just to the impact Margo had on our politics but her impact on our society.

"People are here from the worlds of the arts, entertainment, broadcasting, journalism, numerous campaigning organisations, MPs, MSPs, members of the House of Lords, former and current presiding officers, former first minister Jack McConnell, current First Minister Alex Salmond, and 150 staff from the Parliament itself who have helped organise this wonderful occasion.

"There are people here who are from the right, left and centre of politics, and with no politics at all. There are people here from the No camp, led by Alistair who is very kindly here as well, and from the Yes camp.

"And most importantly, there are Jambos (supporters of Hibs' Edinburgh rivals Hearts) here as well to celebrate the life and achievements of one of Hibs' most famous fans.

"Margo wanted this to be a celebration of her life and only tears of laughter and joy are permitted."

He added: "Can I say to Alex (Salmond), when I spoke to Margo two days before she died, she told me how much she appreciated the extended visit he paid to her home in the last week before she died.

"Alex has said himself in tribute to Margo that she offered him sound advice on how to win the referendum - and he intends to follow it.

"Her death leaves a huge hole not just in the Parliament but in the nation. It is especially sad that she has been denied the chance to put her own stamp on the referendum campaign.

"For the last 41 years, Margo MacDonald has been the flower of Scotland."